Camper van layouts: the order to make decisions in

Every guide to camper van layouts hands you a list of questions. How many people, do you want a shower, where will you cook. Answer all of them honestly and you can still end up with a design that cannot be built, because those questions are not independent and the lists never say which one has to go first. Layout is a sequence, and the order is the whole thing.

Decide in this order

Each of these constrains the next, and none of them constrains the one above it. That is what makes it an order rather than a checklist. Taken out of sequence you will design something, get it priced, and find out it was never possible.

• 1. Bed orientation. Crosswise or lengthwise. It is the only element with a hard external constraint, because a bed cannot be shorter than the person in it. It sets your minimum interior width and therefore usually your chassis.
• 2. Bathroom, yes or no. It takes about nine square feet, it needs a grey tank, and it has to sit where the plumbing can reach it. Deciding this late is the single most common cause of a redraw.
• 3. Garage volume. Set by what you carry, measured, not by preference. A bike with its wheels on is 42in or more of height and that number does not move.
• 4. Seating. Where you sit when it rains for three days. It comes before the galley because a van with nowhere to sit gets rebuilt and a van with a small galley does not.
• 5. Galley size. Whatever is left. This is fourth from the bottom for a reason: a kitchen can be 4ft of counter or 8ft and both work.
• 6. Systems positions. Batteries, tanks, heater and their runs. These fit around the furniture, but they are heavy and they have rules, so they get a veto rather than a preference.

Bed goes first because it is the only decision with an input from outside the van. Everything else can shrink to fit. Once bed orientation is settled, the chassis is usually settled with it, and the five plans that survive that constraint are a much shorter list than the galleries suggest.

The reason seating outranks the galley surprises people. Ask anyone who has lived in a van through a wet autumn and they will tell you the same thing: you can cook badly for a year, and you cannot spend three days sitting on a bed. Layouts get rebuilt over seating far more often than over kitchens.

The measurements, and what each one gates

A list of measurements is only useful if each one has a consequence attached. Take these six, in your own van, with the doors shut.

Width is the one people get wrong, because they take it from a brochure. Mercedes publishes a maximum width at the floor of 70 inches for the Sprinter, which is bare metal at the widest point. Your finished van is 64 to 66 inches across at bed height, and that is the number that decides whether two people can sleep across it.

Wheel arches are the second trap. They are not a nuisance, they are a fixed obstacle that dictates where a bed platform can start and how deep a galley base can be, and a plan drawn on a rectangle will always be wrong at the two points the arches occupy.

Where the weight has to go

A van layout is also a mass distribution problem, and this is the part the layout guides skip entirely. Where you put the heavy things changes how the van drives, and it changes it most in the conditions where you would least like a surprise.

The rule is simple. Heavy, low, and between the axles. A full 30 gallon fresh tank is about 250lb, a lithium bank 100 to 150lb, and both of them want to sit under the floor or under the bed platform ahead of the rear axle rather than at the back of the garage.

The failure case is worth naming because it is common. A tank mounted high or behind the rear axle behaves differently at every fill level, and a half-full tank is worse than a full one because the water moves. On a crosswinded interstate at 65mph with a loaded roof rack, a van set up that way wanders in a way that is tiring at best.

It also affects the plan directly rather than just the drive. Because tanks want to be central and low, the galley and the bathroom want to be near each other, because every foot of pipe run is a foot that can freeze, sag or lose pressure. A layout with the sink at the front and the shower at the back is fighting its own plumbing, and adding a wet bath at the far end of the van is how a sensible plan turns into a long cold water run.

Payload is a layout constraint, not a packing one

This is the arithmetic that ends plans, and almost nobody does it before drawing. Payload is not how much you can pack. It is how much van you are allowed to build, and the build spends most of it.

There is a detail in how the figure is defined that matters and never gets mentioned. NHTSA defines gross vehicle weight rating as not less than the unloaded vehicle weight, plus the rated cargo load, plus 150 pounds multiplied by the vehicle's designated seating capacity. Every seat is 150lb of the manufacturer's own arithmetic before anybody sits in it, which is why adding seats to a conversion costs payload twice: once for the engineered seat base and once in the rating.

Add that column up and a mid-range build for two people lands between 2,200 and 3,350lb. Mercedes publishes maximum payloads from 4,211lb on the 2500 up to 6,812lb on the 4500, and Ford publishes a Transit GVWR range from 8,670 to 11,000lb, so the chassis variant you choose has to be chosen against the layout rather than after it. Overloading is not a technicality either. NHTSA's tire guidance is explicit that the load rating of the tires on an axle must at least equal that axle's rating, and the Tire and Loading Information label on the driver's door edge is where your actual limit is written. Going past it affects braking and handling, and what the van is legally rated to carry is enforceable rather than advisory.

Where the systems want to live

Layout guides treat electrical and water as things that happen after the furniture. They are not. Four systems place real constraints on the plan, and all four are cheap to accommodate at the drawing stage and expensive afterwards.

• Battery to inverter. This run should be as short as physically possible. A 3,000W inverter three metres from the bank needs heavy, expensive cable and still loses voltage. Put them in the same cabinet and the problem disappears.
• Solar to controller. The roof penetration wants to be close to the electrical bay. Every extra metre of run is more cable and one more thing routed through a wall you have already closed up.
• Fan and vent positions. A roof fan wants to be over the galley or the bed, and both positions compete with solar panels for the same flat roof area. Draw the roof at the same time as the floor.
• Heater intake and exhaust. A diesel heater needs an underfloor mount with clearances, and the ducting has to reach the living space without crossing the plumbing.

The roof is the part people forget is a plan at all. Panels, a fan, a rack and an awning all want the same flat area, and a fan placed badly means a solar array that cannot be laid out efficiently. Drawing the roof and the floor together takes an afternoon and saves a specification argument later, which is also where the real cost differences between quotes tend to hide.

One asymmetry is worth planning around. Battery capacity is straightforward to add later if the shop leaves physical room and cable for it, so under-specifying the bank is a recoverable mistake. Solar is not, because adding panels later means going back through a roof that has been sealed, and the same is true of a second roof fan. Anything that puts a hole in the metal should be decided at the drawing stage and nothing that lives inside a cupboard needs to be.

The heater is the one that most often gets placed last and should not be. It needs an underfloor mount with clearance from the fuel tank and the exhaust, and the only sensible positions for that are usually already claimed by the fresh tank, which is competing for the same low, central floor space for the reasons above.

How the plan changes with more than two people

The order above holds for one person and for two. Above two it changes, because a third body introduces a constraint that outranks bed orientation: everyone travelling needs a forward-facing seat with a proper belt anchored to the vehicle structure, and a bench built into a conversion is not a seat unless it was engineered and mounted as one.

That reordering has a knock-on effect worth understanding early. Seats have to be engineered, engineered seats consume payload, and payload was already the tight constraint. It is why a van built around a family starts from the seating plan and works outward, rather than starting from the bed like every other build.

Pets fit into this more easily than people expect, with one exception. A dog needs a secured position while driving and a place to be that is not the walkway, and the second of those is a layout decision. A dog bed in the walkway of a van with 20 inches of floor is a van where somebody steps on the dog every evening.

The mistakes that force a rebuild

• No usable indoor seating. Every layout looks fine in July. The test is three consecutive rainy days, and a bed with cushions against a wall is not a sofa.
• A galley you cannot use with the doors shut. Common in narrow plans. If cooking needs the slider open, you have built a summer vehicle.
• A garage sized from a photograph. Measure the actual bike, wheels on, as it will be loaded. The number is always bigger than the guess.
• Batteries far from the solar and the inverter. Long DC runs need heavy cable, which is expensive, lossy and hard to add later.
• A walkway under 20 inches. It reads as a small compromise on a drawing and it is the thing you resent every single day.
• Bed length set by the mattress rather than the person. A 74in mattress in a 76in space is fine. A 74in mattress and a 76in person is a rebuild.

The common thread is that all six are obvious in a finished van and invisible on a drawing. Which is the argument for not staying on the drawing.

Testing a layout before you commit

Two exercises catch most of it, and together they cost less than a tank of fuel.

Tape the plan out full size on a garage or driveway, at the finished interior width rather than the brochure width. Put a chair where the seat goes and a box where the galley goes. Then spend an evening moving between the positions you would actually occupy: cooking, sitting, getting into bed, getting past the other person while they cook. Most people change something significant within the hour.

Then rent a van with a layout close to the one you have drawn, for a weekend, in bad weather if you can arrange it. A couple of hundred dollars against a build that starts at a median of $58,000 across the 46 shops in our directory that publish pricing is the best-value money in the entire process, and it is the only test that tells you how a plan feels rather than how it looks.

People who do both change their plan almost every time. People who do neither find out during the build, when a change costs weeks as well as money and starts to move how long the whole conversion takes.

What a change costs once the build has started

Timing is everything here, and the cost curve is steep rather than gradual. Before the shop cuts anything, a change is free. After first fix, it is a rebuild of that section.

The practical response is to spend a fortnight on the plan and treat the shop's revisions as the thing you are paying for. Good shops will change what you send them, because they know where the structural mounting points are and how the tank routes work, and the shops doing genuinely bespoke work will push back hardest of all. That pushback is the value, not an obstacle to it.

Key takeaways

• Decide in order: bed, bathroom, garage, seating, galley, systems. Out of order you design the impossible.
• Bed orientation goes first because it is the only element with a constraint from outside the van.
• Measure metal to metal, then take 2in to 4in per side off for walls. A 70in Sprinter finishes at 64 to 66.
• Payload is a layout constraint. A mid-range two-person build lands at 2,200 to 3,350lb, against 4,211lb on a Sprinter 2500.
• Every designated seat costs 150lb in the rating before anyone sits in it.
• Tanks and batteries go low and between the axles, or the van wanders when they are half full.
• Draw the roof at the same time as the floor. Fans and solar compete for the same area.
• A change after first fix costs 40% to 70% of that section again. A fortnight of planning is free.